In addition to meeting with doctors, Beau Biden, his wife and the vice president took time to enjoy the Bayou City. And those who saw them out Monday night say Beau was in good spirits despite being in town for medical testing.

Secret Service vehicles lined the entrance of MD Anderson on Tuesday.

"It's hard to comment without more information about his case. But he wouldn't be coming to MD Anderson after being seen at two excellent institutions for a vascular problem," said Dr. Randy Evans, who's a neurologist.

Raising speculation as to why he'd be visiting a cancer facility. All the White House is confirming is that Beau is undergoing tests after he began feeling weak and disoriented last week. Since then, he's been seen at He was admitted to Northwestern Memorial Hospital in Chicago and then consulted with his own doctor the next morning in Philadelphia.

"It may be unrelated to the reason why he had the spell. So perhaps he had a dizzy spell and tests were done and they found a problem elsewhere in his body. Maybe it wasn't in his brain at all," said Dr. Evans.

Despite his medical issues, Beau tweeted out a picture with his wife, moments before eating a family dinner Monday evening at D'Amico's Italian Market in Rice Village.

"I said, 'What brings you here?' And one of them said, 'We're just here doing some tests,'" said restaurant owner Nash D'Amico.

David Reyes, the Biden's waiter Monday night, says Beau seemed to be in great spirits, even posing for pictures.

"He did not look sickly or anything like that. He managed himself well and you wouldn't know he was sick," Reyes said.

Beau Biden, who is only 44 years old, has had medical issues in the past suffering from a stroke three years ago.

Vice President Biden has himself dealt with health problems -- 25 years ago he underwent surgeries to correct two aneurysms.

It's unclear whether Vice President Biden would remain in Houston overnight or not.

Beau Biden is the eldest son of Vice President Biden. After the 1972 accident that killed his wife and daughter and critically injured brothers Beau and Hunter Biden, the vice president devoted himself to caring for his two sons as a single father.

Beau Biden served a yearlong deployment to Iraq with his Army National Guard unit, returning stateside in 2009.

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